Gear-cutting machine.



F. BURGESS=' GEAR CUTTING MACHINE.

APPLICATION FILED APR. 2, 1913.

Patented June 15, 1915.

e SHEETSSHEET 1.

jzzverzi or".

. Frank Bur e55 11/5 Amrizey F. BURGESS.

GEAR CUTTING MACHINE.

APPLICATION FILED APR-2.1913.

L1%3 5?Um I Patented June 15, 1915.

6 SHEETS-SHEET 2- JQJIIIIIIIII! Frank Bur e55.

5 b W A 1 5 Afiorrmy F. BURGESS.

GEAR CUTTING MACHINE. APPLICATION FILED APR. 2. 1913.

6 SHEETS-SHEET 3.

Wank Burgess 5 024 111 fifnm v 72/5 .ALIWW F. BURGESS.

GEARCUTTING MACHINE. APPLICATJON HLED APR. 2, 1913.

F. BURGESS. GEAR cumwe MACHINE.

APPLICATION FILED APR-2,1913- 9m Patented June 15, 1915.

6 SHEETS-SHEET 5- I I I Frank Bur 655.

by W

F. BURGESS.

GEAR CUTTING MACHINE. APPLICATION FILED APR.2,1913.

l mfi fimm Patented June 15, 1915.

6 SHEETS-SHEET 5- mazes. frwerwar I Frank Bfucyess W bywxhflw 77/5Aflurney 5 I To all whom it may concern ,1

PATENT t me.

'B UJRQESS, QF NORFOLK DOWNS, MASSACHUSETTS.

GEAR-CUTTING MACHINE.

mantra.

Be it known that l, FRANK Boneless, a citizen of the United States, andresident of Norfolk Downs, county of Norfolk, State of Massachusetts,have invented an Improvemen-t in Gear-Cutting Machines, of which thefollowing description, in connection with the accompanying drawings, isa specification, like characters on the drawrepresenting like parts. bepresent invention is a gear cutting machine adapted for the cutting ofvarious kinds of gearing such as spiral, worm and helical gears, and,screws, more particularly by what is known as the hobbing process,wherein the cutting hob is a hardened wheel orv cylinder formedaccording to the shape and dimension of the gear element with which theblank when out is to intermesh, this hob being gashed to form cuttingteeth at suitable intervals.

One of the prime objects of the invention is to provide a constructionwherin chat tering and vibration is substantially eliminated, this beingaccomplished by mounting the cutter head so that the hob has a miniofoverhang and has an absolutely rigid backing directly against thesupporting column, the work carrying arbor being also strongly andrigidly, backed on lts slide ways so that cutter and work are held inprecise alinement and immovable relation producing a smoother finish onthe work than has heretofore been possible, with a virtual eliminationof the effects of jarring and chattering.

A further important object of the invention is to provide a constructionwherein a complete and effective clearance of chips from cutter and workis insured, these together with the lubricant employed in the cutting,falling clear of the operating parts by reason of: the verticalarrangement of the hob, and into a drain pan removably set in thesupporting pedestal, the lubricant draining from this pan into areceptacle provided therefor in the base the arran ement of the hob axisin a vertical plane a so permitting the operator to keep the cuttingaction of the hob under close inspection.

A further object is to provide a simplified form of driving connectionswhereby cut-- ter and work are properly and efi'ectively driven andcontrolled with the smallest possible number of transmittin gears, thedrive being arranged throug ordinary Specification of Letters Patent. Patenflgqgd ung- 15 11915. Application filed April 2, 1913. Serial Ito.7%,387.

gears and straight shafting without requir- 1ng universal joints or like.expedients.

A further object of theinvention is to provide a5 constructionpermitting the use of a special swivel cutter head of known type with asupporting backing therefor in-' volving a very short overhang of thehob, while permitting the hob to be adjusted through a wide range ofangles centrally of its axis of adjustment.

A further object is to provide an improved mounting of cutter head witha range of ad ustments permitting the cutting of spur, spiral, helical,"and worm gears, and screw threads, with a facility and easy capabilityof change from one use to another.

A further object is to provide an improved form of driving connectionswherein the same mechanism is adapted to be employed for changing thegear ratios and also to serve as a belt tightener.

A furtherobject is to provide improved power mechanism for feeding thework table, with an automatic disengaging device' at the end of thetable movement and pro- VlSlOI). for quick return by means of a handoperated device.

A still further object is to provide means drawings and will bethereafter pointed out in the appended claims.

Referring to the drawings, Figure 1' is a front elevation of a machinewherein my improvements are embodied; Fig. 2 is a side I view of theoperative portion of the machine, the supporting pedestal being brokenaway; Fig. 3 is a side view of the machine from the side opposite tothat of Fig. 2; Fig. 4: is a central vertical section through themachine; Fig. 5 is a plan view of the machine; Fig. 6 is a diagrammaticview showing the lines of gearing for operating and controlling thevarious parts, Fig. 7 is a fragmentary elevation showing an end view ofthe throw-out mechanism for the table feed; Fig. 8 is a side elevationof the throw-out for the table feed; Fig. 9 is a fragmentary viewshowing a micrometer adjuster for the hob carriage support; Figs. 10,11, and 12 show a plan, side elevation and end view respectively, of anout-board or rim backing fo'rthe work piece; Fig. 13 is a sectionaldetail of the adjusting mechanism for taking 'up back-lash in the cutterdrive; Fig. 14 is a fragmentary. plan of parts shown in Fig. 13, andFig. 15 is a fragmentary elevation showing the prime driveconnections. ka

The operating parts are shown as mounted'on" a hollow pedest'al'base 1which has a cavity orreceptacle in its bottom as seen at 2 into whichthe lubricant drains and from,

j which supports the cutter head, is adjustably mounted; the arrangementof these slide ways being such as to position the opposite operativeportions of cutter and blank directly over the pan 4 as seen in Fig.4.

The spaced apart slide ways 7 and 9 are thus arranged with the chipreceiving well beneath, therebetween in a horizontal direce tion. Thecolumn 10 isequipped with vertical slide ways 11 on its front face towhich is fitted the cutter carriage slide 12 which is verticallyadjustable on these ways by a manually operated screw rod 13 fitted tothe top of the column as at 14 and having threaded engagement with a lugprojecting back from the slide 12 as seen at 15. The cutter head slide12 has on its front face an undercut annul r groove 16 in which fit theheads of clamp bolts for holding the cutter head 17 in any desiredangular 'position.

' The cutter head 17 has slidably fitted at one side thereof a deadcenter bearing 18 for one end of the cutter arbor, and at an oppositeside it is equipped with a bearing 19 for'the driving bevel gear 20 ofthe hob arbor, this gear being shown as having a sleeve extendingthrough. said bearing within which the hob arbor 21 is removably fixed,the hob 22 being thus mounted centrally and trans versely with referenceto its axis of adjustment about the center 23. The drive for the hob isimparted to the bevel pinion 20 from a bevel gear 24 mounted on shaft25..

arranged concentric withthe axis of cutter adjustment in a bearingsleeve 26 provided therefor in a bracket member 27 bolted to the back ofthe slide 12. The shaft 25 is in driven engagement with a bevel gear 28,

' this driven engagement being effected by a.

driver 35 of the machine.

slidable key connection 29 for apurpose to be presently explained. Thedriving impulse is imparted to the gear 28 from a pinion 30 slidablykeyed on an upright shaft 31 journaled in the bracket 27 and havingfixed at' its lower end one of a pair of bevel gears 32, the other ofwhich is slidably keyed to a horizontal shaft 33 journaled in themachine framework and having spur gear driving connections 34 to theprime k The just described train of connections has provision foreliminating back-lash in the drive to the hob and to accomplish thispurpose with reference to the gears 20, 24 I provide means for adjustingthe shaft 25 which has the gear 24 fixed thereto inward or to the leftin Fig. 4. -For this purpose a screw bolt 36 has ball bearing thrustengagement 37 at its inner end with the outer end of shaft 25, and theouter end of this screw bolt has threaded thereon adjusting and clampingnuts 38 at each side of upstanding arm 39 on bracket 27 through whichthe outer end of screw bolt 36 passes, the intermediate portion of thisbolt being yoked around the vertical shaft 31 as best seen in Fig. 14.Thus, by adjusting the nuts 38 the gears 24, 20 may be brought intoprecisely correct operative relation to a nicety, with the virtualelimination of back-lash, and the parts securely clzimped in thisadjusted position. A like result is attained with reference to the gears28,30, by adjusting screw rings 40 threaded on the end of sleeve bearing26 and adapted to adjust the gear 28 outward by virtue of its slidablykeyed en agement 29 with the shaft 25, the second 0 the nuts 40 servingas a lock nut as is usual in look nut constructions. To permit drivingthe hob at any one of a variety of selective speeds the change gears 34are provided, the driving one of these being mounted on a stud shaft 41to whichthe driving pulley 35 is fixed. This stud shaft 41 is adjustabletoward and from the shaft 33 being clamped in adjusted position in along slot 42 of a radius arm 43 journaled concentric with the shaft 33.This radius arm is adapted to be swung angularly about the shaft 33 as acenter for the urpose of properly tightening the belt w "ch operates onbelt pulley 35 and for this purpose it has a laterally extending lug orear 44 with. a longarcuate slot 45 therein, through which a clamp bolt46 takes, to clamp the arm 43 in position with the driving belt properlytightened.

Driving impulse for rotating the work and also for feeding theworkcarriage endwise is transmitted throu h the shaft 33 and for thispurpose it has xed thereto atits inner end one of a pair of meshing bevl pinions 47 the other of which is fixed to a short counter-shaft 48jornaled in the frame work which has fixed at its other end one of ILitatto a pair of spur gears 49, the other of which is fixed to a, shaftwhich is journaled in the frame work and extends out at the left sidethereof as seen in Fig. 1. This projecting end of shaft 50 has fixedthereon a gear 51 which forms the driving member of a train .of changegears, the intermediate ones of which are journaled on a stud shaft 52adjustable on aradius arm 53 and these change gears on this radius armdriving other change gears on an adjustably'mountedrstud shaft 54 whichtransmit driving impulse to gears fixed on a shaft 55 which extendsacross the machine. One of the gears fixed on shaft 55 constitutes thedriving member of a spur gear train 56 which drives counter shaft'57journaled in the frame work and having a projecting portion in squaredor slidably keyed driving engagement with one of a pair of bevel pinions58, the other of which is fixed tothe end of a shaft 59 journaled in abracket arm 60 to extend upward diagonally, and having at its outerportion a worm 61 fixed thereon which drives a worm wheel 62 fixed onthe work arbor 63.-

The 'worm 61 is adapted to be disengaged from the worm wheel 62 at willand for this purpose the bracket arm 60 is journaled to swing about theshaft as an axis and its other end is equipped with an arcuate slot toreceive a clamping bolt, this slot being of sufficient lengthv to permitthe swinging of the bracket arm to engage or disengage the worm at will.

For the purpose of feeding the work carriage endwise, the shaft 55 isextended across the machine and projects at its right side as seen inFig. 1 where it hasfixed thereon a pinion 64, which through a train ofchange gears'65 and bevel gears 66 drives a shaft 67 journaled in abracket arm 68. The shaft 67 has fixed at its outer end a worm 69adapted to drive a worm wheel 70 fixed on the feed shaft 71 which isjournaled in the frame work beneath and in parallelism with the workcarriage slide 8, said slide having a depending nut 72 in threadedengagement with said feed shaft. To permit disengagemen-t of the worm 69from the worm wheel 70, the bracket arm 68 is .swingingly mounted aboutthe axis 73 of the bevel which the shaft 67 is driven and its outer endhas 'an arcuate slot and clamp bolt device 74 for controlling theposition of the bracket arm at will.- I preferably utilize this swingingmounting of the bracket arm 68 to constitute an automatic throw out ofthe work feed at the end of operative move ment, and for this purposethe clamping connection 74 is loosened and a spring 75 is fixed at oneend to the frame work and con nected at its other end to said arm tonor-- mally draw the arm downward. The bracket arm and worm 69a1'e heldup to operative position while the machine is in gear by from pump toengaging position. 0 trip this latch at the end of work-carriagemovement, I provide a rod 81 adjustably carried in lugs or ears 82 atthe side of the work carriage, and 1n use th1s rod is positioned andclamped in the lugs 82 so that its'end 83 will engage a pro ection 84 atthe top of the latch 76 to trip said latch when the work is completed,and permit the worm 69 to become disengaged from the Worm wheel 70, thusstopping the feed. It will of course be understood that the latch 76 mayalso be tripped by hand to permit disengagementof the Worm 69, thusstopping the feed manually. The work carriage may be convenientlyreturned quickly by hand when its driving gearing is thus disengaged,and for this purpose I show a hand operated crank shaft 85 having abevel gear driving connection 86 to the carriage operating screw 71.

For the purpose of moving the column 10 'with the cutter head-in-and outradially of the work, I provide a manually operable screw shaft 87engaging in a nut 88 depending from said column and having an operatinghand wheel 89 extending out at a convenient position for operation witha micrometer head 90 in position for convenient inspection.

I preferably provide means for furnishing a strong rigid backing to theouter edge or rim portion of the gear blank in the direction of theworking thrusts and adjacent the point being operated on and for thispur pose I show a stout'arm 91 clamped to the upright or post 92 whichcarries the live center of the work arbor, ing of an adjustablecharacter effected by means of .a long slot 93in the arm 91 throughwhich the clamp bolts 94: pass into the upright post. This arm 91 has atits outer end an upstanding portion 95 of a height adapted to present astout pin 96 passing through-its upper end in position to engage the endof the gear blank substantially in the plane of cutting action. 'Thispin 96 is adjustable in the upright portion 95 and for this purpose itis threaded and has fitted thereon nuts 97 adapted to hold it in fixedand definite relation to the arm by which it is carried. Thus by properin and out adjustment of arm 91and by adjustment of the pin 96 in saidarm, the end of the pin may be brought to position to act as a stop andbacking for any size or character of blank for the cutting of which themachine is adapted.

It will be understood that the lubricant 3 is forced up to be dischargedat the cutting point by a suitable piping 98- this clamping beleading toa point adjacent and directly over the cutting point as best seen inFig. 4;. .To

conserve the lubricant as thus discharged and insure its return to thereceptacle in.

the pedestal base and prevent its being scattered from the machine,I-preferably pro-.

videshield or guardplates 99, 100, 101 at eachside ofthe machine,thesebeing adapted to slide over-one another more or less,-. intelescopingfashion, when the column.10 is adjusted in and out; Thusit is insuredthat the lubricant and cuttings-will drop mtothe pan 4 andnot bescattered, since in the first with the receiving pan 4: at the bottomthereof. It is to be observed that these desirable features are combinedwith a construction wherein the cutter head is virtually swiveled to theri 'd frame backing whereby, very great sti ness with very littleoverhang, is attained, .J It is the construction and arrangement of thecutter head 17 with a mounting on a vertical slide way 11 of column 10so that it 1 rests and has backing immediately thereon workman standingin front of the machine over substantially its entire area andwithnothing interposed except as shown the slide plate 12 to permitangular adjustment, that I refer to in the claims when I describe thecutter carrier as having a; direct mounting on its backing support.

It is to be noted that my improved arrangement provides for a continuousclose inspection of the cutting operation by a since the working pointon the work is always in sight from this point; further that thethrow-out controleffect'ed by. the adjustable rod 81 is also mounted atthe front of the machine for convenient access from this position, andthat the out-board work prop" or support carried by arm 91 is alwaysconveniently controllable and adjustable from this position. My improvedconstruction minimizes back-lash in two ways, first by lar ely reducingthe number of gears in the drlving train to the hob, and second inproviding means whereby the bevel gear teeth mesh accurately and closelyas by the adjusting device exemplified by threaded adjusting rod 36; itwill be understood that this adjustment is merely illustrative ofsimilar adjusting means that may be employed throughout in the drivingtrain if desired.

It is, of course, to be understood that the several change gear trainsdescribed are selectively arranged ,and combined in various waysaccording to the character, size and pitch of the gears to be cut themachine as described being capable o tions of the hob and work in anydesired ratios within widelimits; this relative variation beingdistinctively effected. in the present machine by arrangin the severalchange gear trains, in the line 0 driving connection to the work arbor,leaving the drive to the hob a short, direct, and powerful one whichneed not be disturbed by the variations in driving ratio between the hoband work as effected by the change gear devices. The driving movementsto the hob and work arbor may be'combined with a continuous end'wisefeed of the work by movement of the work-carriage slide 8 as effected byfeed screw 71, there being of course in this case a suitablecompensating element introduced in the ratio of rotation between the hoband work, or the work slide 8 may be held stationary by disconnection ofthe driving worm 69 from screw 71 at will, for types of work bestperformed in this way. I am aware that the various features of theinvention can be embodied in other specific forms and in differentrelations from the illustrative embodiment shown and I therefore do notdesire to belimited to the present form of the invention or to anyparticular form and refer to the appended claims rather than td theforegoing description to indicate the scope'of protection intended tobe. secured.

Having described my invention, what I claim as new and desire to secureby Letters Patent is:'

1. A gear cutting machine, comprising a supporting frame work havingspaced apart slideways with an intermediate lubricant and chip receivingwell beneath constituting a lubricant container at its bottom and withan intermediate receptacle for cuttings, a work carrier mounted formovement on one of said slide ways and a cutter carrier mounted formovement on the other slide way directly over said well said workcarrier and cutter carrier bein formed to hold the work and cutterprojecting toward each other with the operative area substantially oversaid well.

2. A gear cutting machine, comprising a frame work having a cutter slideway and a work slide way at right angles to each other with anintermediate lubricant and chip receiving well beneath, there bein alubricant container at the bottom of said well and a receptacle forcuttings removably held thereabove, a cutter slide, and a work slidemounted for movement on their respective slide ways, said slides beingformed and equipped to hold acutter and a'blank respectively with theiroperative areas over said well.

3. A gear cutting machine, comprising a inmates frame work having slideways on its top at right angles to each other, a work carnage slide onone of saidvways, a cutter support slide on the other of said ways, saidframe work having an open chip and lubricant receiving well beneath saidways in chip receiving position, and a hob carrier mounted directly oversaid well, whereby clearance for chips and lubricant is provided.

4.. A gear cutting machine,-cornprising a work carrier, a hole, carrier,driving connections for imparting operative movements to said carriersfor rotating the hob and Work in timed relation, and a mounting for thehob carrier formed to swing in a vertical plane about an axistransversely central of the hob, there being a rigid column upstandingfrom the machine frame work affording a direct rigid backing for saidhob mount ing in all positions of its angular adjustment, and saiddriving connection to the hob carrier being a direct train from a primedriver in part concentric with the axis of said mounting for the hobcarrier.

5; A gear cutting machine, comprising a supporting frame work havingslide ways at right angles to each other at its top, a work carrierslide fitted to one of said slide ways, an upright column fitted to theother slide way, a cutter slide vertically adjustable on said column, ahob carrier mounted for angular adjustment on said slide about an axistransversely central of the hob, said hob carrier and said cutter slidebeing formedand relatively arranged for the hob to have a relativelyclose, direct, and rigid backing on said column with a minimum ofoverhang, whereby vibration is minimized, and means for driving the hobcarrier. formed as a relatively direct train from a prime driver havinga part concentric With the axis of angular adjustment of the hobcarrier.

6. A gear cutting machine, comprising a frame work having slide ways atright angles to each other on its top with an intermediate lubricantand, chip receiving well beneath the same, a work slide on one of saidslide. ways, a cutter support slide on the other slide way, cutter onsaid cutter support located directly over said well, the parts mountedon the cutter slide and the work slide constituting two sides of thewell top, and relatively slida'ble guard plates mounted to inclose theremaining sides of the well top whereby scattering of lubricant andcuttings isprevented.

7. A gear cutting machine, comprising an upright frame work having acutter slide Way and a work slide Way spaced apart with an intermediatewell for lubricant and cuttings beneath the same, a cutter carrier and awork carrier cooperatively mounted on said slide ways respectively andforming two sides of the well top, and plates fixed to-said carrierfitted to slide over each other swinging ,a

frame work support having a for inclosing the remaining two sides ofthewell top whereby scattering of lubricant and cuttings is prevented.

gear cutting machine, hob. carrier and a workcarrier mounted incooperative relation, the work carrier being mounted for. feed movementendwise ofthe work axis, and driving connections for rotating the hoband work in timed relation consisting in a direct and relatively shorttrain of permanently mounted gears for driving the hob and series ofselective change mpris gears connected therewith for rotating the workand feeding it endwise in a predetermined and variable ratio to the hobrotation.

.4 gear cutting machine, comprising a hob carrier and a work carrier,one of said carriers being mounted for feed movement endwise of thework, and driving mechanism for-said carriers consisting in a relativelyshort train ofdirect permanent gears for rotating the hob and series forrotating the work and efi'ecting a relative feed thereof endwise, theconnections for effecting such relative feed having provision forautomatic disconnection at will, said connections also permitting manualdisconnection.

10. A gear cutting machine, comprising a frame work supportrhaving slideways at right angles to each other, a slide having a Work carrier hereonfitted to one of said slide ways, ho carrying means fitted to the otherof said slide ways with provision for swiveling adjustmentabout an axistransversely central of the hob, means for driving the hob in anyposition-of its adjustment, and means for moving the work, said meanshaving provision for rotating the work in any one of a series of ratiosrelative to the hob rotation, and other provision for feeding the workendwise of its axis at predetermined and variable rates. I

11. A gear cutting machine, comprising a frame work support having slideways at right angles to each other, a work carrier mounted on one ofsaid slide ways and formed to present the Work with its axis parallel toand overhanging said slide way and at right angles to the other slideway, and a hob carrier mounted on the other slide way with provision forangular adjustment of the hob in a vertical plane parallel to the workaxis and about central of itself.

12. A gear cutting machine,

comprising a slide way, a work carrier fitted and connected for feedmovement along said slide Way formed to hold a work piece with its axishorizontal and parallel, with said slide Way, and a rotary cuttercarrier mounted to attack the work so held and having provision foradjustment about a vertical axis in a plane parallel to the work axis.

of change gears an axis transversely 13. A gear cutting machine,comprising a base frame Work having a slide way along the front of thetop thereof, a work carrier mounted on said slide way, a hob mounted toattack the. work carried thereby, means for feeding the work carrieralong said slide way, having as a part thereof a'worm and worm wheeldriving connection, said worm being mounted to swing into and out ofoperative relation to said worm wheel, means for holding the wormnormallv in driving In testimony whereof, I have signed my name to thisspecification, in the presence of two subscribing witnesses.

' FRANK BURGESS.

Witnesses:

HARRY H. KERR, GEORGE L. Comm.

